Careful analysis of solution scattering data that we had obtained last year suggested that the P0 protein forms a tetrameric assembly, supporting the tetrameric crystallographic structure of the soluble extracellular domain of P0 by the Hendrickson group. This result was accepted for publication recently. Besides, we measured solution scattering of P0 in SDS at different salt concentrations and pH values to characterize electrostatic properties of the protein, and also mesured the protein solubilized in octyl glucoside.